I do recall noticing this too, so it may well not be a graphics card problem, but an intentional story scripted event, hard to tell. Hope others can confirm, but pretty sure it was also dark for me, although that was a long time ago in my memory to be fair.

I did some research in the meantime. Deliah's tower should be lit up during nights. However the very last patch of the game messed up something, so it's not anymore. But you can watch older gamplays on youtube where it works as it should, before the last patch.

The last update was in 2021, so it seems it will stay broken forever...

well researched - pity, although makes sense since it was not long ago that I re-played the game to look into the missing young boy's story and if that actually changed Henry's life any. A pity